NS 2310 Final TTU

1. sweet- sugars, glycols, alcohols, and aldehydes

2. sour- acids found in foods

3. bitter- caffeine, theobromine (chocolate), phenolic compounds

4. salty- salt ions in NaCl and other salts

5. savory (umami)- glutamate (amino acid)

the 5 taste stimuli

sight (first impression), odor, taste, touch, and hearing

sense used to evaluate food

adaptation

ability to distinguish various odors diminishes over the time of exposure to the smells

sensory (subjective) evaluation

-scientific discipline of measuring the responses of people to food products as perceived by their senses

-often uses human panels

-relies on opinions of the individual

-two types: analytic (effective-based on discernable diff-trained panel) and affective (consumer-detects preferences)

-more expensive and time consuming; vital for product research and development

objective tests

-use laboratory instruments

-quantify physical and chemical differences in foods

-used to analyze content and safety of food

-two types: physical and chemical

-more reliable and repeatable; not subject to human opinion; good for routine quality control

carbs, protein (15%), fat (15-20%), water (60-70%), vitamins, and minerals (12%)

6 basic nutrients and their percentages in the body

hydrolysis

a chemical reaction where water breaks a chemical bond in another substance

-splitting it into two or more new substances

-ex: water added to sucrose to produce glucose and fructose; water added to triglyceride to split it into glycerol and 3 fatty acids

carbon, hydrogen, and oxygen

key elements of carbs

carbon, hydrogen, and oxygen

key elements of fat

nitrogen, carbon, hydrogen, and oxygen

key elements of proteins

-hydration

-denaturation/coagulation

-enzymatic reactions

-buffering

-browning

functions of proteins in foods

complete protein

-usually from animal sources

-provide all 9 essential amino acids

-gelatin is one of the few animal proteins that is not in this category

incomplete protein

-usually from plant sources

-exceptions: soybeans, quinoa, and amaranth

-do not contain all 9 essential amino acids

-heat transfer

-tenderness

-mixing

-texture

-flavor

-inc satiety

functions of lipids in food

-contribute to sweetness (saccharides or sugars)

-starches used as thickening agent, edible film, and sweetener

functions of carbs in food

-transfer medium for heat

-universal solvent

-agent in chemical reactions

functions of water

digestible: starch and glycogen

indigestible: fiber

digestible carbs and indigestible carbs

regulate metabolic functions

functions of vitamins and minerals in food

vitamins

-organic (contain carbon)

-can be destroyed by heat, light, or oxygen

-do not provide energy

minerals

-inorganic

-cannot be destroyed by heat, light, or oxygen

-no energy

cross-contamination

the transfer of bacteria, other microorganisms, or food allergens from one food or surface to another

-ideal for bacterial growth

-consumers: 40-140 degrees F

temperature danger zone

1. shallow containers

2. reduce food size

3. ice-water bath with stirring

4. blast chiller (quickly cools)

proper methods to cool food

moist-heat preparation

-heat is transferred by water, water-based liquids, or steam

-helps to soften fibrous proteins in meat and cellulose in plants

-liquid can contribute to flavor, color, texture, and appearance

-methods incl. scalding, poaching, stewing, braising, boiling, and steaming

color, flavor compounds, vitamins, and minerals may leach out and be lost in the liquid

drawbacks of moist-heat preparation

dry heat preparation

-heat transferredby air, radiation, fat, or metal

-uses higher temps b/w 212 and 500

-methods incl baking, roasting, broiling, grilling, barbecuing, and frying

-3

-2

-8

-2

-2

-4

___ tsp = 1 T

___ T= 1 oz

___ oz= 1 C

___ C= 1 pint

___pints = 1 quart

___ qts= 1 gallon

-whole-grain and graham flours and meal bc it will remove the bran particles

which type of flour should not be sifted and why?

descriptive

-listed in the sequence in which they are used

-displays ingredients, amounts, and directions in 3 columns

standard

-lists all the ingredients and amounts with the instructions in numerical order

action

-gives the instructions followed by the ingredients for that step only

narrative

-reads like an essay, explaining ingredients, amounts, and preparation methods in text

-overpurchasing: 3 day rule for perishables

-losses from food prep: purchased vs. edible portion

-losses from shrinkage during cooking: percentage yield

-portion control: losses from plate waste

reduce waste by considering:

meat (highest expense), fish, dairy, bread/grains, fruits and veggies, price comparisons

focus on these areas to keep food costs down:

-low in: calories, cholesterol (none), sodium, and fat

-high in: carbs (incl. fiber), vitamins and minerals

-incomplete source of protein

-higher vitamin and mineral content than fruits

-dark green, leafy: riboflavin, beta-carotene, vitamin C and iron

-green veggies: vitamin K and folate

general nutrient content of fresh vegetables

-types

-when to use

-optimal characteristics

-consider the season of the year when selecting

important selection considerations from purchasing vegetables

fruit

-the ripened ovaries and adjacent parts of a plant's flowers

-type determined by the type of flower: simple (drupes: apricots, cherries, peaches: pomes: apples, pears), aggregate (blackberries, raspberries, strawberries), multiple (pineapple, figs)

-denature enzymes

-add acid

-lowering temp

-coat fruits

-adding antioxidants

how to slow/inhibit enzymatic browning

-water (75%)

-7 g of protein per oz (20%)

-fat varies widely across types and cuts (varies)

-contain few carbs

-excellent source of B vitamins

-excellent source of iron, zinc, copper, and phosphorus

nutrient content of meat

inc exercise = inc collagen (connective tissue) = dec tenderness

relationship between exercise, connective tissue and tenderness of meat

1. cut of meat

2. age of animal at slaughter (younger=more tender)

3. animal's heredity

4. diet (grain fed more tender)

5. marbling (more marbling=more fat=more tender)

6. slaughtering conditions (timing and duration of stress)

7. aging (holding meat after slaughter to improve texture and tenderness, improves juiciness, tenderness, flavor, color, and browning ability)

factors which effect meat tenderness

-best for tender cuts of meat

-place fat side up

-300-350

-18-30 min per 1 lb of meat

-remove slightly before cooked

general roasting recommendations for meat

-myoglobin content determines color

-myoglobin = dark (slow-twitch muscles)

effect of myoglobin and hemoglobin on coloring of poultry

ducks and geese have higher fat content than chickens or turkeys (inc their buoyancy in water)

duck and goose nutrient content compared to chicken or turkey

-sniff test: "fresh fish" aroma- safest and easiest

-tight scales

-firm flesh

-stiff body

-red gills

-belly free of swelling or gas

criteria for selecting fresh fish

-cooking too long

-cooking at too high temp

common mistakes when cooking seafood

-generally lower in fat than other meats

general nutrient content of meat from fish

-shell- 12%- calcium carbonate

-yolk- 30% (all fat soluble vitamins)

-albumen- 58%

-shell membranes- protect from bacteria

-air cell- bw shell membrane

-chalaza (part of albumen technically) - anchors yolk

-cuticle or bloom- waxy coating on eggshell that protects against bacterial contamination and water loss

composition of eggs

white stock

-flavored liquid obtained by simmering the bones of beef, veal, chicken, or pork in water

may:

-omit egg yolk

-replace egg yolk with vegetable oil

-remove some cholesterol in egg yolk

how liquid egg substitutes are made

-gentle so that air is not forced out

folding egg whites

brown stock

-stock resulting from browning bones and/or meat prior to simmering them

stock

-foundational thin liquid of many soups produced when meat, poultry, seafood and/or their bones, or veggies are reduced (simmered) and strained

bouillon

-broth made from meat and veggies and then strained to remove any solid ingredient

consomme

-richly flavored soup stock that has been clarified and made transparent by the use of egg whites

1. rinse greens to remove soil

2. remove water by draining, patting with paper towel, or using a salad spinner

3. remove stems or core of greens

4. refrigerate for at least 30 min to promote crispiness

5. hand tearing leaves is preferred to reduce bruising

preparation of a quality leafy green salad

1. hydration (hydrate in cool water before heating to prevent clumping)

2. dispersion (hot water (100 degrees F) or stock can be added to disperse the protein granules; stir often

3. gelation (refrigerate- will first convert to a sol (liquid consistency) and cooling further will create more solid-like gel

phases of gel formation

1. heat transfer

2. shortening power (tenderizes)

3. emulsions

4. varying melting points

5. plasticity

6. solubility

7. flavor/mouthfeel

8. textures

9. appearance

10. satiety

11. nutrients

functions of fat in food

-plant foods: avocado, nuts, seeds, olives

-processed foods

-animal products: red meat, milk, cheese

where do we find abundant amounts of fats and oils?

-fats are solid at room temp; oils are liquid

-fats are generally from animals; oils generally from plants

fats vs. oils

UHT

-ultrahigh temperature pasteurization combined with sterile packaging procedures

-280-302 for 2 seconds

-kills more bacteria and extends shelf life

-refrigeration not required until opened (up to 3 months)

homogenization

-prevents separation of water and fat

-mechanical process that breaks up fat globules in milk into smaller globules that do not clump together and are permanently dispersed in a very fine emulsion

-87.4% water

-6.6 pH

-carbs: lactose- 12 g per 8 oz

-complete protein source- 8 g per cup: casein and whey

-milk fat

-86-150 cal/cup; 0-8 g fat

-cholesterol: 33 mg in whole, 18 mg in red fat, 4 mg in non-fat

-vitamins A and D and B2 (riboflavin)

-thyptophan (important in forming niacin)

-calcium, phosphorus, potassium, magnesium

-low in iron

nutrient content of milk

-according to bacterial count

-grade A-lowest count

-voluntary

how is milk graded?

granule

-the plants cell unit for storing starch

-differ in shape and size

*cheese sauce

white sauce

some gravies

examples of thickened sauces

other gravies

hollandaise

butter sauce**

fruit

bbq

tartar

tomato sauce

examples of unthickened sauces

-thickening agent

-edible films

-dextrose (sweetener)

-starch syrups

uses of starch

roux

-foundation of thickened sauces

-equal parts fat and flour

-three types: brown, blond, and white

-as this cooks it becomes darker and its starchy taste lessens

beurre manie

-equal parts butter and flour

-mixture not cooked

-slowly whisked into a simmering sauce

-use only small amount to prevent taste from becoming starchy

slurry

-combine starch and cool liquid (cornstarch or flour)

-mix into simmering liquid base (sauce thickens)

-may yield starchy taste

-less stable thickening

flour, pasta, breakfast cereals, alcoholic beverages, and animal feeds

uses of cereal grains

-husk: rough outer covering

-bran: hard outer covering under husk; protects endosperm; excellent source of fiber and minerals

-endosperm: largest portion of grain (83%); contains starch

-germ: embryo; fat incomplete protein, vitamins and minerals

composition of grain kernels

cooking gelatinizes the starch- this occurs when heated starch molecules absorb water and expand and swell 2-3 times in volume

principle behind cooked pasta expansion

-removes the husk, bran and germ

-leaves only endosperm (starch)

-nutrients lost during refining:

thiamine, riboflavin, niacin, vitamin B6, pantothenic acid, folate, vitamin E

effect of refining on grain nutrients

-good source of soluble and insoluble fiber

-phytochemicals, lignans, and phytoestrogens

-low in the essential amino acid lysine

nutrient content of whole grains

-sweetens

-protective coating

-inc volume via incorporating air in fat

-food for yeast

-raises temp at which gelatinization and coagulation occurs which gives gluten more time to stretch = more volume

-inc moistness, tenderness

-browning

-too much: baked products fall, have low volume, a gummy texture, and excessively browned crust

-too little: dry, reduced browning, low volume and less tenderness

effect of sugar in flour mixtures

-improves volume, texture, evenness of crumb, shelf-life

-too much inhibits yeast activity

-too little results in low volume, uneven cell structure and bland taste and color

effect of salt in flour mixtures

-tenderizer

-inc: vol, structure/strength, flakiness, crumb, flavor and color

-delays staling

-too much: fluid batter, weak structure, dec volume

-too little: resistant to expansion during leavening, tough crumb

effect of fat in flour mixtures

-enhance structural integrity

-contribute to: leavening, color, flavor, and nutrient content

-too much results in tough, rubbery texture

-too little: not enough volume

effect of egg in flour mixtures

-compresses and stretches dough

-evenly distributes yeast

-warms dough which inc fermentation and CO2 production

-yields a smooth, stretchable dough

-gluten formation

-avoid kneading too much- can cause sticky, lumpy dough with little elasticity

purpose of kneading

1. hydration: gliadin + glutenin = gluten (formed when the addition of water causes these two proteins to combine and form gluten)

2. kneading

gluten formation

gluten

protein portion of some grains such as wheat, rye, or barley

celiac's disease

allergy to gluten

-physical: air and steam

-biological: yeast and bacteria

-chemical: baking powder and baking soda yield CO2 when the alkali reacts with an acid in the presence of liquid

(mostly by CO2 produced from biological/chemical sources-primarily by yeast)

types of leavening agents

flour and water

what is the simplest flour mixture

milk, fat, eggs, sugar, salt, flavoring, leavening agents

what other ingredients can be added to flour mixture

1. dry: flour, leavening agents, sugar, and salt/flavorings

2. liquid: milk, water, fat, eggs

categories of ingredients that can be added to flour mixture

structure, volume, taste, texture, appearance, and nutrient content

types and proportions of flour mixtures determine what?

straight dough

-mixing method for yeast bread

-place all ingredients in bowl at the same time, mixed, rise once or twice

sponge

-mixing method for yeast bread

-combine yeast, water, and 1/3 of the flour; allow to ferment in warm place .5-1 hour; add remaining ingredients

batter

-mixing method for yeast bread

-simplest; combine ingredients; beat via hand or electric blender

rapid

-mixing method for yeast bread

-mixes in bread maker

flour, liquid, sugar, salt and yeast

fat and eggs optional

fundamental ingredients in yeast breads

when it is doubled in size and two fingers in dough leave indentation

when is the first rise done?

leavened by CO2 produced by yeast

leavener used in all yeast bread production and its function

shortened

-aka butter or conventional cakes, leavened with baking powder or baking soda

-cake made with fat

unshortened

-aka sponge or foam cakes; leavened with beaten egg whites

-cake made without added fat

chiffon

-shortened and unshortened hybrid

-cake made from fat from vegetable oil and egg yolks and combine with foamed egg whites

-volume inc by expanding air, steam and CO2

-structure sets: protein coagulates and CHO gelatinizes

-crust browns via maillard rxn and caramelization of sugars

-fat melts

-heat flows from edges toward the center of the pan, so cakes become rounded at the top as their interiors continue to rise after the outside portions of the cake have started to set

changes during baking of cakes